JP2007504316A - Fuel composition containing Fischer-Tropsch derived fuel - Google Patents

Abstract

Fischer-Tropsch derived fuel is used in the composition for the purpose of reducing the amount of additives, particularly antifoam and / or defogging agents, in the fuel composition. Fischer-Tropsch fuel reduces the amount of silicon-containing additives in the composition, generally lowering the silicon level, and thus reducing the atomization of fuel and / or reducing the efficiency of combustion in the fuel consumption system operating with the fuel composition. And / or can be used to reduce deposits in the system, especially silicon deposit build-up. The Fischer-Tropsch derived fuel is preferably a gas oil and the fuel composition is preferably a diesel fuel composition.
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Description

  The present invention relates to fuel compositions, particularly automotive fuel compositions such as diesel fuel compositions, methods for their production and use, and methods for using certain types of fuels in fuel compositions for new purposes.

  Conventional diesel fuel contains liquid hydrocarbon middle distillate fuel oil having a boiling range of about 150-400 ° C. Examples of such fuels include Fischer-Tropsch methane condensation methods, such as Shell Middle Distillate Synthesis (shell middle distillate synthesis) (van der Burgt et al., “The Shell Middle Distillate Synthesis”, 5th. Reaction products of Synfuels Worldwide Symposium, Washington DC, November 1985; see also the November 1989 publication of the same title by Shell International Petroleum Company Ltd., London, UK). Such Fischer-Tropsch derived gas oils are low in undesirable fuel components such as sulfur, nitrogen and aromatics, and when blended with other diesel fuels such as petroleum derived gas oils when used as automotive fuels, Easy to reduce automobile emissions.

  Diesel fuel compositions currently used in common diesel engines tend to contain one or more additives to improve their performance and properties. Examples of this type of additive include cleaning agents that can help reduce and / or remove combustion-related engine deposits, defoamers that reduce foaming while refueling the engine, and suspended water from the fuel. Examples include dehazing agents that aid in removal.

  In this regard, however, it may be desirable to reduce the level of these additives in the fuel composition. This can be tracked by consumer preference and / or technical or economic considerations.

  Antifoaming agents that are usually used preferably in automotive fuels are based on silicone. Silicon is found in deposits that accumulate in diesel engine fuel injectors. Excess deposits in fuel injectors can interfere with fuel atomization and combustion, and thus overall engine efficiency, so reduce the use of any material that may contribute to deposit formation. Is desirable. There is no clear link between using antifoam and nozzle contamination, but the risk of potential problems can be reduced if alternative methods can improve antifoam performance.

In addition, defoamers that do not contain silicon are known, but when used in fuel compositions containing detergents, they tend to be less functional and are therefore suitable for use in commercially available ordinary diesel fuel compositions. Is inappropriate.
GB-A-960493 EP-A-0147240 EP-A-0482253 EP-A-0613938 EP-A-0557516 WO-A-98 / 42808 GB-B-2077289 EP-A-0147873 EP-A-0583836 US-A-4125556 US-A-4478955 EP-A-1101813 WO-A-97 / 14768 WO-A-97 / 14769 WO-A-00 / 20534 WO-A-00 / 20535 WO-A-00 / 11116 WO-A-00 / 1111 WO-A-01 / 83406 WO-A-01 / 83641 WO-A-01 / 83647 WO-A-01 / 83648 US-A-6204426 van der Burgt et al., "The Shell Middle Distillate Synthesis", 5th Synfuels Worldwide Symposium, Washington DC, November 1985 paper.

  Thus, fuels with low silicon levels or preferably containing additives that do not contain silicon, without undue degradation of defoaming performance or undue impact on other fuel properties such as defogging performance and cleaning performance. It may be desirable to provide a composition, particularly a diesel fuel composition. It may also be desirable to provide fuel compositions that generally contain low levels of additives, particularly antifoaming agents, defogging agents and / or cleaning agents.

  We have a particular fuel component itself, both alone and blended with other fuel components, having defoaming properties, defogging properties and / or cleaning properties. It has now been found that it can be used to replace all or at least some of these additives in the fuel composition.

  In a first broadest aspect, the present invention provides a method of using a Fischer-Tropsch derived fuel in a composition for the purpose of reducing the amount of additive (or additive other than a detergent) in the fuel composition. . In other words, the Fischer-Tropsch derived fuel replaces the additives present in the fuel composition, preferably at least partly because it serves at least part of the normal and / or intended function of these additives. May be used.

In particular, Fischer-Tropsch derived fuels may be used to reduce the amount of antifoam and / or defogging agent in the composition. This derived fuel may be used to reduce the amount of silicon-containing additives (particularly silicon-containing antifoaming agents). This induction fuel is preferably used to reduce the amount of cleaning agent.
More generally, this derived fuel may be used to reduce the amount of silicon in the fuel composition.

  The ability to reduce additive levels using the present invention provides many advantages. Obviously, the blending cost of the fuel composition can be reduced. You may appeal this to consumers. Furthermore, the potential for (possibly harmful) interactions between various additives that may have been incorporated together in the composition can be reduced. Secondly, an effective fuel-additive combination can be made easier to formulate and more flexibility can be added to possible additive combinations. It may even be possible to contain additives that have been excluded due to interaction with other components in the composition.

  As a result of using a Fischer-Tropsch derived fuel in the composition, additives that may or may not be included may include, for example, lubricity enhancers, ignition modifiers, rust inhibitors, corrosion inhibitors, rhedolants ( rheorants), antiwear additives, antioxidants, metal deactivators, antistatic agents, pipeline drag reducers, flow improvers, wax antisettling agents and mixtures thereof.

  In some contexts, the Fischer-Tropsch derived fuel may be a Fischer-Tropsch derived naphtha or kerosene fuel, but gas oil is preferred. The fuel composition is preferably an automotive fuel composition, more preferably an automotive fuel composition for an internal combustion engine, most preferably a diesel fuel composition.

  In the context of the present invention, “using” a Fischer-Tropsch derived fuel in a fuel composition is advantageous prior to introduction of the composition into an internal combustion engine or other system operating with the fuel composition, It is meant that the Fischer-Tropsch derived fuel is introduced into the fuel composition, usually as a blend (ie, physical mixture) along with one or more other fuel components and / or fuel additives. “Use” also means that the Fischer-Tropsch derived fuel itself is used as the fuel composition.

  In this context, the term “reduction (including reduction or reduction)” or “reducing” means reduction to zero. In other words, the Fischer-Tropsch derived fuel may be used to partially or completely replace related materials. This reduction is relative to the level of related additives introduced into the composition to achieve the necessary and / or desired properties and performance in relation to the intended use of the fuel composition. Good. This level was present in the fuel composition and / or contained other similar fuel compositions, for example, before realizing the use of Fischer-Tropsch derived fuel according to the method provided in the present invention. Prior to increasing the amount of Fischer-Tropsch derived fuel, it may be the level of additive present in other similar fuel compositions intended for use in similar situations (eg, to market).

  For example, in the case of a fuel composition intended for use in an automobile engine, specified to meet the current fuel specifications and / or to protect engine performance and / or to satisfy consumer demands A minimum defoaming property, defogging property and / or cleaning property may be desirable. The present invention can at least partially use a Fischer-Tropsch derived fuel in place of the additives necessary to achieve these properties.

  Thus, in connection with a reduction in the level of an additive that has a specific effect on the overall properties or performance of the fuel composition, a Fischer-Tropsch derived fuel may at least partially share its effect on behalf of the additive. May be used to accomplish by itself. The resulting composition contains low levels of additives, but without any associated property or performance degradation or undue degradation, preferably even with improvement.

  Fischer-Tropsch derived fuel reduces the w / w concentration of the relevant additive, preferably by at least 10%, more preferably at least 20 or 30%, even more preferably at least 50 or 70 or 80 or even 90% Used for. As mentioned above, the relevant additive may be completely replaced, in which case the concentration of such additive in the composition is 0% w / w, ie the fuel composition does not contain the relevant additive.

For example, the concentration of the defoamer remaining in the fuel composition is 10 ppmw (parts by weight per million) or less, preferably less than 10 ppmw, more preferably 5 ppmw or less, still more preferably less than 5 ppmw, even more preferably 4 or Furthermore, you may use in order to substitute an antifoamer to the grade used as 3 ppmw or less. Most preferably, the defoaming is such that the fuel composition contains little or essentially no such additive, for example the antifoam content is 2 ppmw or less, preferably 1 ppmw or less, more preferably 0.5 ppmw or less. It may be used to replace the agent almost completely.
(All additive concentrations mentioned herein refer to the active concentration unless otherwise specified.)

  An “antifoaming agent” is suitable for inclusion in a fuel composition (for example, a diesel fuel composition), for example, an agent having an effect of improving the defoaming characteristics of the composition as described below, or such an agent. It means a formulation containing a reagent. Known silicone-based antifoaming fuel additives include TEGOPREN ™ 5851 (from Goldschmidt), Q 25907 (from Dow Corning), SAG ™ TP-325 (from OSi) and RHODORSIL ™ (Rhone Poulenc). There are polyether-modified polysiloxanes available as commercial products such as Known silicone-free antifoaming agents include various alcohols, (poly) ethers and (poly) acrylates such as Laurex ™ DF (from A & W), HD-Ocenol ™ 70/75 (from Henkel) , X702 (from Mobil), Nalflo ™ 71-D5 (from Nalloc) and Unem ™ 4420 (from Unichema).

  Alternatively or additionally, the Fischer-Tropsch derived fuel generally has a concentration of silicon-containing additives, particularly silicon-containing antifoams, in the fuel composition of generally 10 ppmw or less, preferably 5 ppmw or less, more preferably 4 ppmw or less, even more preferably 3 or 2 ppmw or less may be used to reduce. Also, the fuel composition contains little or essentially no such silicon-containing additive, for example silicon-containing additive is 1 ppmw or less, preferably 0.8 ppmw or less, more preferably 0.5 or even 0.1 ppmw or less. As such, it may be used to almost completely replace such silicon-containing additives. Most preferably, the fuel composition does not contain silicon-containing additives, especially silicon-containing antifoam agents (ie 0% v / v).

  As a result of using Fischer-Tropsch derived fuel in this manner, the amount of silicon in the fuel composition is ideally less than 1000 ppbw (parts by weight per billion), preferably less than 500 ppbw (ideally less), Preferably no more than 400 or 300 or 200 ppbw, even more preferably no more than 100 or 50 or even 20 or 10 ppbw, most preferably no silicon or at least a slight trace amount that can contribute to the prevention of environmental pollution (dust) It is.

  The Fischer-Tropsch derived fuel may be used to replace the defogging agent to an extent that the concentration of the defogging agent remaining in the fuel composition is 15 ppmw or less, preferably 10 ppmw or less, more preferably 5 ppmw or less. Most preferably, the fuel composition contains little or essentially no such additive, for example the defogging agent content is 3 ppmw or less, preferably 2 ppmw or less, more preferably 1 or even 0.5 ppmw or less. Indeed, it may be used to almost completely replace the defogging agent.

  “Defoaming agent” is suitable for inclusion in a fuel composition (eg, diesel fuel composition), for example, an agent having the effect of improving the defogging properties of the composition, as described below, or such It means a formulation containing a reagent. Known defogging agents include alkoxylated phenol formaldehyde polymers such as NALCO ™ EC5462A (formerly 7D07) (from Nalco) and TOLAD ™ 2683 (from Petrolite) as commercial products.

  “Detergent” means a detergent or detergent-containing formulation suitable for inclusion in a fuel composition (eg, a diesel fuel composition). A cleaning agent is an agent (preferably a surfactant) that can act to remove and / or prevent deposition of combustion-related deposits in a fuel combustion system, particularly an engine fuel injection system such as an injector nozzle. . Such materials are sometimes referred to as dispersible additives.

  Examples of known detergents include polyolefin substituted succinimides or succinamides of polyamines such as polyisobutylene succinimide or polyisobutylene amine succinamide, aliphatic amines, Mannich bases or amines and reaction products of maleic anhydride (eg polyisobutylene) Is mentioned. Succinimide dispersible additives are described, for example, in GB-A-960493, EP-A-0147240, EP-A-0482253, EP-A-0613938, EP-A-0557516 and WO-A-98 / 42808. . Detergent-containing diesel fuel additives are known and are commercially available from, for example, Infineum (eg F7661 and F7685), Octel (eg OMA 4130D) and Lubrizol (eg Lz8043 series).

  When the fuel composition contains a cleaning agent, the concentration of the cleaning agent is usually 20 to 500 ppmw, more preferably 40 to 500 ppmw, most preferably 40 to 300 ppmw or more as an active cleaning agent, based on the total fuel composition. It is the range of 100-300 ppmw or 150-300 ppmw. However, in the context of the present invention, the detergent is present at a low concentration relative to the total fuel composition, such as preferably 400 ppmw or less, 300 ppmw or less, more preferably 200 or 100 ppmw or less, most preferably 50 or 20 ppmw or less, such as 10 It may be used with -100 ppmw or 10-50 ppmw active detergent. The cleaning additive present is incorporated at a level below the recommended standard single rate, preferably below the rate, more preferably below 0.8 times the treatment rate, and even more preferably below 0.5 times. It is preferable. Even more preferably, the fuel composition does not contain a cleaning agent.

A second aspect of the present invention provides a Fischer-Tropsch derived fuel in the composition for the purpose of improving the defoaming and / or defogging properties of the fuel composition, preferably for the purpose of further improving the cleaning properties of the composition. Provide a way to use. This improvement may also be related to the relevant properties of the fuel composition and / or other similar fuel compositions contained prior to realizing the use of Fischer-Tropsch derived fuel according to the method provided in the present invention. • Before increasing the Tropsch derived fuel, it may be compared to the relevant properties of other similar fuel compositions intended for use in similar situations (eg on the market).
The fuel composition is preferably an automobile fuel composition that is usually used in an internal combustion engine, and more preferably a diesel fuel composition. The Fischer-Tropsch derived fuel is preferably a gas oil.

  The defoaming properties of the fuel composition may be evaluated with respect to the volume of foam generated when a sample of the composition is filled into a suitable container and / or the rate at which the generated foam disappears. Such parameters may be determined using standard methods such as the Association Francais de Normalization (AFNOR) method NF M 07-075 and / or tests based on such a method, such as the method used in Examples 1 and 2 below. May be used and evaluated.

  An improvement in defoaming properties may be represented by a decrease in foam volume and / or a decrease in foam extinction time or foam collapse time (same as an increase in foam extinction rate) when the fuel composition is tested in this manner. Fischer-Tropsch derived fuels contain the same fuel composition except that they do not contain Fischer-Tropsch derived fuels or contain some amount (preferably 5% v / v or less, more preferably 1% v / v or less). For the same volume of foam generated under the same test conditions and / or before replacing some or all of the antifoam in the fuel composition according to the invention with a Fischer-Tropsch derived fuel, The foam volume reduction is preferably 2% or more, more preferably 4% or more, still more preferably 6 or 10% or more, most preferably 12 or 15 or 20% or more, relative to the foam volume generated below. Used in an amount sufficient to achieve 22 or 25% or less.

  Fischer-Tropsch derived fuels contain the same fuel composition except that they do not contain Fischer-Tropsch derived fuels or contain some amount (preferably 5% v / v or less, more preferably 1% v / v or less). Same for the same fuel composition before the foam extinction time indicated under the same test conditions and / or before replacing some or all of the defoamer in the fuel composition according to the invention with a Fischer-Tropsch derived fuel The reduction (shortening) of the foam extinction time relative to the foam extinction time indicated under the test conditions is preferably 15% or more, more preferably 18% or more, most preferably 20 or 30 or 40% or more, even 50 or It is used in an amount sufficient to achieve 60 or 70 or 75% or less.

  Fischer-Tropsch derived fuel is tested according to the Association Francais de Normalization (AFNOR) method NF M 07-075 or a test based on this method, for example a test such as Examples 1 and 2 below. When used, the foam volume is preferably used in an amount sufficient to achieve 105 ml or less, more preferably 100 ml or 90 ml or less. It is also used in an amount sufficient to achieve a foam extinction time of preferably 50 seconds or less, more preferably 40 or 35 seconds, even more preferably 30 or 25 or 20 or 15 seconds or less under the same test conditions. .

  The defogging or water removal properties of the fuel composition can be obtained by mixing a sample of the composition with the aqueous phase and determining the appearance of the resulting fuel and / or aqueous phase for a suitable standing time (eg 2 hours or more, preferably 3 or Evaluation may be made by observation after 4 or 5 hours). Poor defoaming characteristics are manifested in particular by a more “cloudy” fuel layer containing suspended water droplets and / or a two-layer boundary with less distinction. In addition, if the volume of the aqueous layer decreases after standing, compared to the original volume added to the fuel sample, it may be represented by more loss (decrease) of the aqueous phase in the fuel layer (for example, If the fuel contains certain oxygenates that help improve miscibility with the aqueous phase, water may be absorbed into the fuel and still not cloudy).

  Alternatively or additionally, the defogging properties can be determined using a Karl Fischer or similar instrument for the water content of the resulting fuel layer after an appropriate standing time (eg, 12 hours or more, preferably 24 hours or more). You may evaluate. In order to evaluate such parameters, a specific fuel composition, such as standard test methods such as ASTM method D1094 (“aviation fuel water reaction”) or a revised version thereof such as the method used in Examples 4-6 below, is used. Improved methods may be used for combined use with products.

  Thus, an improvement in defogging properties may be represented in the aforementioned type of test by an improved visual appearance (less fogging) of the stationary fuel and / or aqueous layer and / or its interface. Alternatively or additionally, it may be represented by a loss of water lost in the fuel layer and / or a reduction in water content in the stationary fuel layer.

  Fischer-Tropsch derived fuels contain the same fuel composition except that they do not contain Fischer-Tropsch derived fuels or contain some amount (preferably 5% v / v or less, more preferably 1% v / v or less). The improvement observed under the same test conditions and / or the same fuel composition before replacing some or all of the defogging agent or other additive in the fuel composition in accordance with the present invention with a Fischer-Tropsch derived fuel Preferably sufficient to achieve at least noticeable improvement, more preferably at least 30% improvement, even more preferably at least 50% or 75% or 100% improvement compared to the improvement shown under the same test conditions Used in large quantities.

  Fischer-Tropsch derived fuels contain the same fuel composition except that they do not contain Fischer-Tropsch derived fuels or contain some amount (preferably 5% v / v or less, more preferably 1% v / v or less). Before reducing the fuel layer water content indicated under the same test conditions and / or replacing some or all of the defogging agent or other additive in the fuel composition in accordance with the present invention with a Fischer-Tropsch derived fuel Preferably at least 5%, more preferably at least 9 or 10%, most preferably at least 15 or 20 or 30 or 40 for the reduction in fuel layer water content exhibited by the same fuel composition under the same test conditions. Or 50%, or even 60 or 70 or 75% or less, or more than sufficient to achieve a fuel layer water content reduction.

  Fischer-Tropsch derived fuel has a fuel layer water content of preferably 120 mg / kg or less after standing for 24 hours when an 80 ml sample of a fuel composition is tested as described above with 20 ml of aqueous buffer under ambient conditions. More preferably it is used in an amount sufficient to achieve 110 or 100 mg / kg or less, still more preferably 90 or 80 or 50 or 40 or 30 mg / kg or less. Preferably, after standing for 4 hours under the same conditions, it is used in an amount sufficient that the weight loss of the aqueous buffer to the fuel layer is not visually detectable.

  For kerosene fuels, a suitable test for defogging properties may be the Institute of Petroleum test method IP 452 (“Measurement of water removal properties (WASP) of aviation kerosene”). In this method, the pass / fail boundary is a residual water content of ˜500-600 mg / l, so a low value represents good performance. In the present invention, the Fischer-Tropsch derived fuel contains no Fischer-Tropsch derived fuel or some amount (preferably less than 5% v / v, more preferably 1% v / v when tested in this manner. The remaining water content obtained with the same fuel composition under the same test conditions and / or some or all of the defogging agent or other additive in the fuel composition according to the present invention. Prior to replacement with Tropsch derived fuel, preferably at least 20% less, more preferably at least 30% less, still more preferably 40 or less than the residual water content obtained under the same test conditions with the same fuel composition. Used in an amount sufficient to achieve a residual water content of 50 or 60% less. Under such test conditions, the residual water content is suitably 500 mg / l or less, preferably 400 or 350 mg / l, more preferably 300 mg / l or less, even more preferably 250 or 200 or even 180 mg / l. Used in an amount sufficient to achieve:

  The cleaning properties of the fuel composition or the cleaning properties of the fuel additive in the fuel composition have an effect on the level of combustion-related deposits in the system when the fuel combustion system (eg, diesel engine) is operated with the composition. You may rate in relation to Such deposits can, for example, accumulate in the fuel injection system of the engine and contaminate the injector nozzle. The cleaning effect is represented by a reduction in contamination when the previously formed nozzle contamination is caused by operating this contaminated engine with the associated fuel composition. Thus, improved cleaning performance is achieved by running a contaminated engine with a fuel composition produced in accordance with the present invention for a predetermined time, and the resulting reduction in contamination does not contain Fischer-Tropsch derived fuel or a small amount (preferably 5% v / v or less, more preferably 1% v / v or less) with the same fuel composition operating the system for the same time and under the same conditions, and / or according to the invention in the fuel composition Operating in the same manner with the same fuel composition prior to replacing some or all of the cleaning agent or other additive with Fischer-Tropsch derived fuel, expressed by greater than the reduction in contamination if it occurs. Good.

  Alternatively or additionally, an improvement in cleaning performance can be achieved by reducing the build-up rate of engine contamination with no Fischer-Tropsch derived fuel or a small amount (preferably less than 5% v / v, more preferably 1% v / v). v)) with the same fuel composition, operating the system for the same time and under the same conditions, and / or according to the invention, some or all of the defoamer in the fuel composition is Fischer-Tropsch derived fuel The same fuel composition prior to replacement with may be operated in the same manner and expressed as a reduction in the rate of contaminated deposition when it occurs.

  The degree of nozzle contamination can be visualized in a number of ways, for example by measuring the amount of contamination on the contamination nozzle or by measuring the fluid flow (eg fuel flow, more preferably air flow) characteristics of the contamination nozzle relative to the clean nozzle. May be evaluated.

  Appropriate testing is the steady state of the engine as a result of using the fuel composition under test in a suitable engine, such as a diesel engine, based on changes in the flow rate of air flowing through one or more fuel injector nozzles. Under the conditions, the degree of nozzle contamination (the shape of the injector contamination index% is convenient) can be measured. These results are conveniently averaged over all of the engine injector nozzles. The CEC standard test method F-23-T-00, which includes an injector nozzle air flow measurement method, may be used, for example, to evaluate engine contamination.

  A Fischer-Tropsch derived fuel preferably reduces the engine contamination (measured as described above) to contain no Fischer-Tropsch derived fuel or a small amount (preferably less than 5% v / v, more preferably 1). Operating in the same fuel composition (under the same or equivalent conditions, for the same time), and / or according to the present invention, cleaning agents or other additives in the fuel composition At least 5%, preferably at least 8%, compared to the reduction in pollution if it occurs when similarly operating with the same fuel composition prior to replacing some or all of this with Fischer-Tropsch derived fuel More preferably, an amount sufficient to reduce by at least 10%, most preferably at least 20% is included.

  More preferably, the Fischer-Tropsch derived fuel is another automobile fuel (usually does not contain Fischer-Tropsch derived fuel or is small (preferably 5% v / v or less, more preferably 1% v / v or less). A sufficient amount to remove the combustion-related deposits deposited on the fuel injection system of the engine, particularly the injector nozzle. This concentration is preferably at least 5%, more preferably at least 10%, most preferably at least 15 or 20 or 25%, relative to previously formed injector deposits (eg, measured as described above). The concentration is sufficient to remove.

  Combustion-related deposit removal can be achieved by using a Fischer-Tropsch fuel-containing composition, for example, conveniently at the same time as deposit deposition under equivalent conditions, more preferably 75% of deposit deposition time, Even more preferably, it can be achieved by operating for 50% or even 40% or 30% of the time. Ideally, combustion-related deposits are at least partially removed by operating the engine with a Fischer-Tropsch fuel-containing composition for 5 hours or less, preferably 3 hours or less, more preferably 2 hours or less. Is done.

  In carrying out the present invention according to the first or second aspect, the fuel composition consists essentially of a Fischer-Tropsch derived fuel in order to achieve the desired objective. In other words, the fuel composition contains a large proportion of Fischer-Tropsch derived fuel (this ratio is preferably 99% v / v or more, more preferably 99.5% v / v or more, most preferably relative to the fuel composition. 99.8% v / v or more, meaning 100% or less) and optionally, one or more suitable fuel additives as known in the art (but ideally Contains a small percentage of non-foaming agents, defogging agents and / or cleaning agents, but no other fuel components.

  Alternatively, the fuel composition contains, in addition to Fischer-Tropsch derived fuel, for example one or more other conventional fuel components, such as diesel base oil (which may itself comprise a blend of two or more diesel fuel components). May be included.

  The concentration of Fischer-Tropsch derived fuel in the composition is selected to achieve the desired defoaming and / or defogging and / or cleaning properties, but also other properties required for the overall composition It may also be affected by (eg density, cetane number and / or release performance).

  The concentration of Fischer-Tropsch derived fuel in the composition is preferably 15% v / v or more, more preferably 20% or 25% v / v or more, still more preferably 30% or 40%, based on the total composition. Or it is 50% v / v or more. Moreover, it may be 40% or 50% or 60% or 70% or 80% or 90% or 95% or 98% v / v or less based on the total composition. Suitable concentrations are, for example, either 20-90% v / v or 25-80% v / v or 25-50% v / v, or 30-70 or 60 or 50% v / v.

  Any of the additional fuel components in the composition may be conventional fuels. These fuel components, ideally also the entire fuel composition, for example low or ultra low sulfur fuels with a sulfur content of 500 ppmw or less, preferably 350 ppmw or less, most preferably 100 or 50 ppmw or less, or even 10 ppmw or less, Or the fuel which does not contain sulfur is preferable.

  For diesel fuel, for example, normal diesel fuel components include liquid hydrocarbon middle distillate fuel oil, such as petroleum-derived gas oil. These fuel components are not Fischer-Tropsch derived, but can be derived organically or synthetically. The boiling range of this type of fuel is the normal diesel range 150-400 ° C., depending on grade and application.

When used in a diesel composition, the fuel component has a density of 0.75 to 0.9 g / cm ³ at 15 ° C., preferably 0.8 to 0.86 g / cm ³ (eg ASTM D4502 or IP 365). The cetane number (ASTM D613) is 35 to 80, more preferably 40 to 75. Usually, the initial boiling point is in the range of 150-230 ° C, and the final boiling point is in the range of 290-400 ° C. The kinematic viscosity at 40 ° C. (ASTM D445) may suitably be 1.5 to 4.5 cSt (mm ² / s).

Fischer-Tropsch derived fuel and other fuel components (when present in the composition) are preferably liquid under ambient conditions.
Where the Fischer-Tropsch derived fuel is a gas oil, this fuel is preferably used as a diesel fuel. Its components (or most of it, eg 95% w / w or more) must be within the boiling range of normal diesel fuel (“gas oil”), ie about 150-400 ° C. or 170-370 ° C. I must. Preferably, the 90% w / w distillation temperature is 300-370 ° C.

“Fischer-Tropsch derived” means that the fuel is a synthetic product of a Fischer-Tropsch condensation process or a derivative thereof. This Fischer-Tropsch reaction is usually carried out at elevated temperatures (eg 125-300 ° C., preferably 175-250 ° C.) and / or high pressures (eg 5-100 bar, preferably 12-50 bar) in the presence of a suitable catalyst. Converts carbon monoxide and hydrogen to long chain, usually paraffinic, hydrocarbons.
n (CO + 2H ₂ ) = (— CH ₂ —) _n + nH ₂ O + thermal If desired, hydrogen: carbon monoxide ratios other than 2: 1 may be used.
Carbon monoxide and hydrogen, themselves, may be derived from either organic or inorganic, natural or synthetic sources, usually natural gas, or organically derived methane.

  Gas oil, naphtha and kerosene products are obtained directly from the Fischer-Tropsch reaction, or obtained indirectly, for example, by rectification of a Fischer-Tropsch synthesis product or from a hydrogenated Fischer-Tropsch synthesis product. Hydrogenation can be performed by hydrocracking to adjust the boiling point range (see, for example, GB-B-2077289 and EP-A-0147873) and / or hydrogen whose temperature flow characteristics can be improved by increasing the proportion of branched-chain paraffins. Isomerization can be included. In EP-A-0583836, a Fischer-Tropsch synthesis product is first subjected to hydroconversion under conditions that do not substantially undergo isomerization or hydrocracking (hydrogenation of olefin components and oxygen-containing components). And then hydrotreating at least a portion of the resulting product under conditions such that hydrocracking and isomerization occurs to produce a substantially paraffinic hydrocarbon fuel. The law is described. The desired gas oil fraction may subsequently be isolated, for example by distillation.

  In order to improve the properties of the Fischer-Tropsch condensation product, polymerization, alkylation, distillation, cracking-decarboxylation, isomerization and hydrogenation, for example as described in US Pat. No. 4,125,566 and US Pat. No. 4,478,955 Other post-synthesis treatments such as modification may be employed.

  The catalyst for synthesizing a Fischer-Tropsch paraffinic hydrocarbon usually contains a metal of Group VIII of the periodic table, particularly ruthenium, iron, cobalt, or nickel, as a catalytically active component. Suitable catalysts of this kind are described, for example, in EP-A-0583836 (pages 3, 4).

  An example of a Fischer-Tropsch-based method is the method known as SMDS (Shell Middle Distillate Synthesis) (shell middle distillate synthesis) (van der Burgt et al., “The Shell Middle Wild Synthesis Synthesis”, 5th Annual , Washington DC, November 1985; see also the November 1989 publication of the same title by Shell International Petroleum Company Ltd., London, UK). This method (sometimes referred to as Shell ™ “Gas-to-Liquid” or “GtL”) involves the conversion of natural gas (primarily methane) derived synthesis gas into heavy long chain hydrocarbon (paraffin) wax. To produce a product in the middle distillate range. After conversion, the hydrocarbon wax can subsequently be hydroconverted and rectified to produce a liquid transportation fuel such as a gas oil that can be used in a diesel fuel composition. Currently, a revised SMDS process that utilizes a fixed bed for the catalytic conversion process is used in Bintulu, Malaysia, and the product is blended with petroleum-derived gas oil in commercial automotive fuels.

  Gas oil, naphtha fuel and kerosene produced by the SMDS method are commercially available from, for example, the Royal Dutch / Shell corporate group. Further examples of Fischer-Tropsch derived gas oils are EP-A-0583836, EP-A-1101813, WO-A-97 / 14768, WO-A-97 / 14769, WO-A-00 / 20534, WO -A-00 / 20535, WO-A-00 / 11116, WO-A-00 / 11117, WO-A-01 / 83406, WO-A-01 / 836341, WO-A-01 / 83647, WO-A -01/83648 and US-A-6204426.

  The Fischer-Tropsch derived gas oil according to the invention is suitably at least 70% w / w, preferably at least 80% w / w, more preferably at least 90% w / w, most preferably at least 95% w / w. Consisting of an isomeric and linear paraffin. The weight ratio of isoparaffin to normal paraffin is preferably greater than 0.3 and may be 12 or less, preferably 2-6. The actual value of this ratio is measured in part by the hydroconversion process used for the production of gas oil from Fischer-Tropsch products. Some cyclic paraffin may also be present.

  By the Fischer-Tropsch process, Fischer-Tropsch derived gas oil is essentially free of sulfur and nitrogen or contains undetectable levels. These compounds containing heteroatoms tend to act as poisons for Fischer-Tropsch catalysts and are therefore removed from the synthesis gas feed. Thereby, the fuel composition produced according to the present invention provides other advantages in terms of effects on catalyst performance.

  Furthermore, the Fischer-Tropsch process does not produce or substantially does not produce aromatic components in normal operation. The aromatic content in the Fischer-Tropsch derived fuel is usually less than 1% w / w, preferably less than 0.5% w / w, more preferably 0.1% w / w as measured by ASTM D4629. Is less than.

  In general, polar components in Fischer-Tropsch derived fuels, particularly polar surfactants, are at relatively low levels compared to, for example, petroleum derived fuels. This is considered to be due to the improvement of the defoaming and antifogging performance of the Fischer-Tropsch derived fuel. Examples of these polar components include oxygenates, sulfur and nitrogen-containing compounds. Low levels of sulfur in Fischer-Tropsch derived fuels are generally indicative of low levels of both oxygenates and nitrogen-containing compounds since both oxygenates and nitrogen-containing compounds are removed by the same process.

The Fischer-Tropsch derived gas oil that can be used in the present invention usually has a density of 0.76 to 0.79 g / cm ³ at 15 ° C. and a cetane number (ASTM D613) of more than 70, preferably 74 to 85. The kinematic viscosity (ASTM D445) is 2 to 4.5 at 40 ° C., preferably 2.5 to 4.0, more preferably 2.9 to 3.7 cSt (mm ² / s), and contains sulfur. The amount (ASTM D2622) is 5 ppmw or less, preferably 2 ppmw or less.

  Preferred products are those that use a hydrogen / carbon monoxide ratio of less than 2.5, preferably less than 1.75, more preferably 0.4 to 1.5, and ideally a Fischer It is produced by a Tropsch methane condensation reaction. Preferably obtained from a hydrocracked Fischer-Tropsch synthesis product (for example described in GB-B-2077289 and / or EP-A-0147873 mentioned above), more preferably EP-A mentioned above The product of the two-stage hydroconversion process as described in -0583836. In the latter case, preferred features of the hydroconversion process may be those disclosed in EP-A-0583836, pages 4-6 and in the examples.

  When the Fischer-Tropsch derived fuel is a naphtha fuel, it may be a liquid hydrocarbon middle distillate having a final boiling point of usually 220 ° C. or lower, preferably 180 ° C. or lower. The initial boiling point is preferably higher than 25 ° C, more preferably higher than 35 ° C. Its components (or most of them, eg 95% w / w or more) are generally hydrocarbons of 5 or more carbon atoms, usually paraffinic.

  Such distillation characteristics of naphtha fuel tend to be comparable to that of gasoline. As with the corresponding gas oil, Fischer-Tropsch derived naphtha fuels tend to have fewer undesirable fuel components such as sulfur, nitrogen and aromatics.

In the context of the present invention, the Fischer-Tropsch derived naphtha fuel has a density of 0.67 to 0.73 g / cm ³ at 15 ° C. and / or a sulfur content of 5 ppmw or less, preferably 2 ppmw or less. It is preferable to contain 95% w / w or more of iso- and normal paraffins, preferably 20 to 98% w / w or more of normal paraffins. Preferably it is a product of the SMDS process, and its preferred characteristics are as described above in connection with Fischer-Tropsch gas oil.

  When the Fischer-Tropsch derived fuel is a kerosene fuel, it is a liquid hydrocarbon middle distillate fuel with a distillation range of preferably about 150-250 ° C or about 150-200 ° C. The final boiling point is usually 190-260 ° C., for example 190-210 ° C. for the usual “narrow fraction” kerosene fraction, or 240-260 ° C. for the usual “all fractions”. The initial boiling point is preferably 140 to 160 ° C. Fischer-Tropsch derived kerosene fuels also tend to have fewer undesirable fuel components such as sulfur, nitrogen and aromatics.

Fischer-Tropsch derived kerosene fuel density 0.730~0.760g / cm ³ at 15 ° C., for example a narrow fraction of a fraction 0.730~0.745g / cm ^3, a fraction of the total fraction 0. 735 to 0.760 g / cm ³ and / or sulfur content is 5 ppmw or less. Preferably it is a product of the SMDS process, and its preferred characteristics are as described above in connection with Fischer-Tropsch gas oil.

When practicing the present invention using a Fischer-Tropsch derived fuel, the gas oil as used in Examples 1, 2, 4-6 below, or the same or similar defoaming and / or defogging properties and / or A gas oil having cleaning properties and / or the same or similar density and / or the same or similar cetane number is convenient.
In accordance with the present invention, two or more of the Fischer-Tropsch derived fuels described above may be used in the fuel composition.

  The present invention is suitable for use in and / or intended for use in any system that powers or otherwise consumes a fuel composition, particularly a diesel fuel composition. Particularly suitable for use in internal combustion or external combustion (preferably internal combustion) engines, more particularly as automotive fuel, most preferably for use in compression ignition (diesel) type internal combustion engines and / or use May be intended. Such diesel engines may be of direct injection type, for example rotary pumps, in-line pumps, unit pumps, electronic unit injectors or ordinary rail types, or indirect injection types. It may be a heavy or light diesel engine.

If the fuel composition is such an automotive diesel fuel composition, it preferably falls within the current standards available, such as EN 590: 99. Preferably, the density is 0.82-0.845 g / cm ³ at 15 ° C., the final boiling point (ASTM D86) is 360 ° C. or less, the cetane number (ASTM D613) is 51 or more, and the kinematic viscosity at 40 ° C. (ASTM D445). ) Is ^{2 to} 4.5 cSt (mm ² / s), the sulfur content (ASTM D2622) is 350 ppmw or less, and / or the total aromatic content (IP 391 (mod)) is less than 11.

  In general, any fuel component or fuel composition may or may contain an additive as long as it is desired to use Fischer-Tropsch derived fuels to reduce the level of additive in connection with the present invention. It does not have to be. Such additives may be added to the base fuel at various stages during the manufacture of the fuel composition. In the case of automotive fuels, for example, additives added to the base fuel at refineries include antistatic agents, pipeline drag reducers, flow improvers (eg ethylene / vinyl acetate copolymers or acrylate / maleic anhydride). Copolymers) and wax anti-settling agents (eg “PARAFLOW” (eg from PARAFLOW ™ 450, from Infineum), “OCTEL” (eg from OCTEL ™ W 5000, Octel) and “DODIFLOW” (eg from DODIFLOW (™) ) V 3958, commercially available from Hoechst).

  Thus, if the fuel composition contains an additive, it is usually not always necessary to incorporate the additive at one or more refineries or downstream thereof with one or more fuel components (including Fischer-Tropsch derived fuel). Preferably, however, the composition contains a small percentage of these additives (preferably less than 1% w / w, more preferably less than 0.5% w / w (5000 ppmw), most preferably 0.2% w / w). / W (less than 2000 ppmw).

  Ingredients that may be incorporated into fuel additives, especially diesel fuel additives, include lubricity enhancers such as EC 832 and PARADYNE ™ 655 (from Infineum), HITEC ™ E580 (from Ethyl Corporation) and VEKTRON (from Trademark) 6010 (from Infineum) and amide-based additives such as those available from Lubrizol Chemical Company, for example as LZ 539 C; ignition modifiers (cetane improvers) (eg 2-ethylhexyl nitrate (EHN), cyclohexyl nitrate, diester Tert-butyl peroxide and those disclosed in US Pat. No. 4,208,190, column 2, line 27 to column 3, line 21); rust inhibitors (eg Rhein Chemie, Mannh) im, a propene-1,2-diol half ester of tetrapropenyl succinic acid commercially available as "RC 4801" in Germany, or a fatty acid of 20 to 500 carbon atoms substituted or unsubstituted at one or more of the alpha-carbon atoms A polyhydric alcohol ester of a succinic acid derivative having an aromatic hydrocarbon group, such as a pentaerythritol diester of a polyisobutylene-substituted succinic acid; a corrosion inhibitor; a reodorant; an antiwear additive; an antioxidant (eg, 2,6- Phenols such as di-tert-butylphenol or phenylenediamines such as N, N′-di-sec-butyl-p-phenylenediamine); and metal deactivators.

  In practicing the present invention, when the fuel composition, particularly a diesel fuel composition, contains any additive, particularly when the sulfur content in the composition is low (eg, 500 ppmw or less), the fuel composition is at least lubricated. It is particularly preferable to contain a property enhancer. Such lubricity enhancers are conveniently present at a concentration of 50 to 1000 ppmw, preferably 100 to 1000 ppmw, based on the total fuel composition.

If there is an ignition modifier, its (active component) concentration is preferably 600 ppmw or less, more preferably 500 ppmw or less, and conveniently 300 to 500 ppmw.
Unless otherwise stated, according to the desire to reduce the level of additives using Fischer-Tropsch derived fuels as well, the (active) concentration of other types of additives in the total fuel composition is preferably 1 % W / w or less, more preferably in the range of 5 to 1000 ppmw, advantageously in the range of 75 to 300 ppmw, for example 95 to 150 ppmw.

  A third aspect of the present invention provides a Fischer-Tropsch derived fuel and / or said induction to reduce fuel atomization and / or combustion efficiency degradation in a fuel consumption system operating or operating with a fuel or fuel composition. A method of using a fuel-containing fuel composition is provided. “Consuming fuel” includes using fuel as power.

  A fourth aspect of the present invention provides a Fischer-Tropsch derived fuel and / or containing the derived fuel in order to reduce the accumulation of deposits, particularly silicon deposits, in fuel consumption systems operating or operating with fuels or fuel compositions. A method of using the fuel composition is provided.

  In the third and fourth aspects of the present invention, "using" a fuel or fuel composition includes introducing it into the system and preferably further operating the system with the fuel or fuel composition. . In this context, “using” a Fischer-Tropsch derived fuel means blending it into a fuel composition, usually together with one or more other fuel components and / or fuel additives (ie, physical). And incorporating the composition into a fuel consuming system, and preferably further comprising operating the system with the fuel composition. Alternatively, using may include introducing the Fischer-Tropsch derived fuel alone into the system and preferably further using it to operate the system.

  In the third and fourth aspects, the fuel consumption system is preferably a fuel combustion system including an internal combustion engine for automobiles such as a diesel engine or a part thereof, in particular a fuel injection system for such an internal combustion engine. It's okay. The deposits in question are prone to deposit in fuel injection systems such as in or around the injector nozzle.

  The efficiency of fuel atomization and / or combustion in fuel-powered systems (usually fuel combustion) is related to the efficiency of fluid flow through the atomization nozzle, eg, as described above, in connection with injector contamination. You may evaluate. Deposits accumulated in the nozzle reduce the flowable area of the fluid and thus the atomization and combustion efficiency. A suitable method for measuring the air flow in the injector nozzle is ISO 4010-1977.

Fuel atomization and / or combustion efficiency can also be represented by a decrease in power output and / or an increase in undesirable emissions from systems such as automotive systems driven by combustion engines.
The preferred degree of fuel atomization and reduced combustion efficiency may be as described above in connection with nozzle contamination for the first and second aspects of the invention.

  Preferably, the Fischer-Tropsch derived fuel is fuel atomized and / or reduced in combustion efficiency, operating the system for the same time under the same test conditions with non-Fischer-Tropsch derived fuel, and / or Fischer-Tropsch derived Operating the system in the same manner with the same fuel composition, except that it contains no or a small amount (preferably less than 5% v / v, more preferably less than 1% v / v) and / or the present invention In accordance with the same fuel composition before replacing some or all of the defoamer, defogging agent, cleaning agent and / or other additives in the fuel composition with Fischer-Tropsch derived fuel And is preferably sufficient to reduce by at least 2%, more preferably at least 5% or 8% or 10% compared to the resulting fuel atomization and / or reduced combustion efficiency. It is used in the preferred situation (context) for an amount, and / or reduced.

  The level of deposits in the fuel consuming system can be measured with the fuel or fuel composition in question over the operating time of the system, for example using a scanning electron microscope and / or X of the system components (especially the fuel injector nozzle). Evaluation may be by line or other spectroscopic analysis.

  Preferably, the Fischer-Tropsch derived fuel operates the system under the same test conditions for the same time with non-Fischer-Tropsch derived fuel and / or contains no or a small amount (preferably 5%) of the Fischer-Tropsch derived fuel. v / v or less, more preferably 1% v / v or less) with the same fuel composition operating in the same manner and / or according to the present invention, Fischer-Tropsch derived fuel in the fuel composition Replace the same fuel composition prior to inclusion or, for example, some or all of the defoamer, defogging agent, cleaning agent and / or other additives in the fuel composition with a high level of Fischer-Tropsch derived fuel Suitable to operate the system in the same manner with the same fuel composition prior to reducing the amount of silicon deposits produced and / or to reduce It is used in the situation.

Preferably, the Fischer-Tropsch derived fuel is used in an amount and / or situation sufficient to produce no or negligible silicon deposits in a fuel injection system operating with fuel or fuel composition. The
This reduction may be assessed over any suitable test time, for example over 10 operating hours, preferably over 100 or 200 or 500 operating hours. It may also be evaluated over the life or expected life of the system, for example, 5,000 operating hours or less for a general passenger car, or 50,000 operating hours or less for a commercial vehicle or stationary generator.

  A fourth aspect of the present invention provides a Fischer-Tropsch derived fuel in a fuel consumption system, preferably in the combustion chamber of the system, for one or more of the purposes described above in connection with the first through third aspects of the present invention. Provided is a method of operating a fuel consumption system comprising the step of introducing a contained fuel composition. The system also preferably includes an internal combustion or external combustion engine, more preferably an internal combustion engine, most preferably a diesel engine.

  The fifth aspect of the present invention encompasses a method of operating a machine powered by a fuel combustion system, particularly a motor vehicle driven by a combustion engine, particularly a diesel-powered motor vehicle.

  In particular, the third to fifth aspects of the invention relating to the nature and concentration of Fischer-Tropsch derived fuel, the nature and concentration of other fuel components and additives present in the fuel composition, and the degree of achievement of any intended purpose. Preferred features may be as described above in connection with the first and second aspects of the invention.

  The sixth aspect of the present invention provides a method for producing a fuel composition comprising blending a Fischer-Tropsch derived fuel with one or more other fuel components and / or one or more fuel additives. This blend is ideally associated with the first to fifth aspects of the present invention, or the effect of the fuel composition on the characteristics of the fuel composition and / or the fuel consumption system in which it is or is intended to be introduced. For one or more of the purposes described above in connection with

  Preferred features of the sixth aspect of the invention, particularly with respect to the nature and relative proportions of the blend (including fuel additive if present), may be as described above in connection with the first to fifth aspects of the invention.

The seventh aspect of the present invention is:
i) contains a Fischer-Tropsch derived fuel and a defoamer that is free or substantially free of silicon, optionally with one or more other fuel components, preferably free of detergents, or ii A) Defoamer containing a Fischer-Tropsch derived fuel and one or more fuel additives, preferably non-cleaning additives, optionally together with one or more other fuel components And / or no silicon-containing antifoam and / or no defogging agent, preferably no detergent, or iii) Fischer-Tropsch derived fuel and one or more fuel additions A non-detergent additive, optionally with one or more other fuel components, and no defogging agent, or iv) Fischer-Tropsch derived fuel And one or more non-detersive fuel additives, together with one or more other fuel components, optionally containing substantially free or free silicon,
A fuel composition is provided.

  The nature and concentration of the fuel additive and additional fuel component (if both are present) may be as described above in connection with the first through sixth aspects of the present invention. For example, in the case of choices (ii) and (iii), the one or more fuel additives are antifoaming agents, defogging agents, lubricity enhancing agents, ignition modifiers, rust inhibitors, corrosion inhibitors, reodorants. May be selected from the group consisting of antiwear agents, antioxidants, metal deactivators, antistatic agents, pipeline drag reducers, flow improvers, wax antisettling agents and mixtures thereof. These can usually be diesel fuel additives. Also, these are generally not oxygenates (oxygen-containing compounds, especially substances having groups such as —OH or C═O or —C (O) O—, which are added to increase the oxygen content of the fuel). . The additive may not contain diesel fuel ignition modifiers such as organic nitrates and / or nitrites.

In relation to the silicon content, “substantially free” intends that the silicon content is 50 ppbw or less, preferably 20 or 10 ppbw or less.
If the composition of the seventh aspect of the invention does not contain a predetermined type of additive, it may instead contain only a low level of the relevant additive. In the case of an antifoaming agent, the low level may be, for example, 300 ppmw or less, preferably 200 or 100 ppmw or less. In the case of a defogging agent, the low level may be, for example, 10 ppmw or less, preferably 5 ppmw or less. In the case of cleaning agents, the low level may be, for example, 100 ppmw or less, preferably 50 or 20 ppmw or less.

The composition of the seventh aspect of the present invention may be produced by the method of the sixth aspect and / or the method described above in connection with the first to fifth aspects.
The eighth aspect of the present invention provides a method of operating a fuel consumption system comprising the steps of introducing the fuel composition of the seventh aspect into a fuel consumption system, and preferably operating the system with the composition.

  A ninth aspect includes a step of introducing a fuel composition produced by performing any one of the first to sixth aspects of the present invention into a fuel consuming system, and preferably a step of operating the system with the composition. A method for operating a consumption system, in particular an internal combustion engine such as a diesel engine, is provided. Such fuel compositions are preferably free of defoamers and / or silicon-containing additives and / or defogging agents, more preferably free of detergents, and even more preferably free of any additives. For each additive, the composition may contain only a low level of the additive, as described above in connection with the seventh aspect of the invention, instead of not containing the relevant additive. The composition is preferably free or substantially free of silicon.

  Other preferred features of the seventh, eighth and ninth aspects of the invention may be as described above in connection with the first to sixth aspects.

The tenth aspect of the present invention provides
(A) to reduce fuel atomization and / or reduction in combustion efficiency in a fuel consumption system operating or operating with fuel or fuel composition, and / or (b) operating with fuel or fuel composition Or the purpose of reducing deposits, particularly silicon deposits, in the operating fuel consumption system;
Provides a method for using a Fischer-Tropsch derived fuel and / or a fuel composition containing the derived fuel.

  In this context, “using” a particular level of silicon includes producing a fuel composition that includes the level of silicon (which may include removing silicon or silicon-containing components from the composition), and And / or operating a fuel consumption system with such a fuel composition.

  The reduced level of silicon may be compared to the silicon level introduced into the composition to achieve the necessary and / or desired properties and performance for the fuel composition in relation to the intended use of the fuel composition. This level was present in the fuel composition and / or similar situations before realizing the reduction of the silicon level, for example to achieve the effects (a) and / or (b) obtained with the present invention. It may be the level of silicon that was present in other similar fuels or fuel compositions intended for use (eg, on the market).

  This reduction level is preferably achieved by reducing the concentration of additives, particularly antifoam agents, in the fuel composition. “Reduced level” includes no or substantially no silicon.

  Other preferred features of the tenth aspect of the present invention, for example with respect to the nature and use of the fuel composition and fuel consumption system, and the degree of achievement of any intended purpose, are discussed above in connection with the first through ninth aspects of the present invention. As you did.

  The invention will be further understood from the following examples. These examples illustrate the defoaming and anti-fogging effects of Fischer-Tropsch derived fuels alone and blends with conventional petroleum derived fuels, and their potential use in fuel systems, particularly diesel engines.

Example 1
Fischer-Tropsch (SMDS) derived gas oil F1 was blended in various proportions with conventional petroleum derived ultra-low sulfur diesel fuel F2, and the defoaming properties of raw fuels F1 and F2 with these blends were evaluated.
Both fuels are commercially available and supplied by the Royal Dutch / Shell corporate group. The characteristics of these fuels are shown in Table A.

Gas oil F1 is obtained from a Fischer-Tropsch (SMDS) synthesis product by a two-stage hydroconversion process similar to the process described in EP-A-0583836.
The defoaming performance of each fuel or blend was evaluated using a test method based on the Association Francais de Normalization (AFNOR) method NF M 07-075. A 100 ml sample of fuel or blend was pumped under controlled conditions into a graduated cylinder as defined in NF M 07-075 and the volume of foam produced was measured. The foam then collapsed and its disappearance time was recorded.
The results are shown in Table 1.

  It can be seen that the incorporation of Fischer-Tropsch derived fuel F1 provides a significant defoaming advantage, especially in terms of reduced bubble extinction time, compared to the performance of petroleum derived diesel fuel F2 alone. The defoaming performance of F1 is significantly better than F2.

Example 2
The defoaming performance of F1 was compared with other commercially available petroleum derived diesel fuels F3-F7. The characteristics of these fuels are summarized in Table B. These fuels were selected to represent a range of different diesel fuel qualities. The suppliers of F3, F4, F5 and F7 are the Royal Dutch / Shell corporate group. The supplier of F6 is Argentina, which corresponds to the typical production quality of the region.

  The defoaming performance of each fuel was tested in the same manner as in Example 1, and the performance of F1 was retested. The results are shown in Table 2.

  The defoaming properties of Fischer-Tropsch derived fuel F2 are clearly superior to all other commercial petroleum derived diesel fuels in both initial foam volume and in particular the foam extinction rate. Furthermore, it can be seen from Example 1 that the defoaming performance of the blend can be remarkably improved by incorporating a small amount of F1 into the petroleum-derived diesel base fuel by about 30% v / v compared to the base fuel alone.

  Thus, according to the present invention, the Fischer-Tropsch derived fuel component can be used to at least partially replace conventional antifoam agents such as silicone-based additives in diesel fuel compositions. This potentially allows a completely antifoam-free composition and still has acceptable total antifoaming performance, as well as reducing the silicon content to a negligible, not zero, Fuel compositions having the advantages described in connection with Example 3 below are possible.

  Furthermore, from these results, as described above, the level of additives, particularly antifoaming agents, is reduced, and the defoaming properties are not unacceptably deteriorated, and Fischer-Tropsch derived gas oil alone is used as a diesel fuel. It turns out that there is a possibility.

Example 3
The potential effects of silicon-containing additives in diesel fuel compositions were observed with diesel engines.
The fuel injector of the Volvo ™ D16A diesel engine was examined with a scanning electron microscope (SEM) according to normal use time running with standard commercial (UK) diesel fuel. This type of fuel has a strong tendency to contain silicone antifoam agents.

  Silicon deposits were detected in the small holes in the fuel injector. This was confirmed by SEM photographs and X-ray analysis of the injector surface performed simultaneously. From the basic structure of the injector metal, the silicon content was 0.34% w / w in the portion not affected by the fuel contact. In contrast, the silicon content at the outer end of the nozzle injection hole was 8.16% w / w. At these levels, there is a significant deposition of elements assumed to be derived from fuel additives through the injector and simple environmental contamination (dust, sand, etc.).

  Such deposits can reliably contribute to fuel atomization and / or reduced combustion efficiency when used for long periods of time. Also, as fuel injection holes continue to tend to become smaller in this type of engine, such deposit build-up may become a more serious problem. Thus, any fuel power system with a fuel injection system can be used, but it is desirable to be able to use fuels with a low silicon content, preferably without silicon, especially in automotive diesel engines. From Examples 1 and 2, it can be seen that the present invention can be used to obtain such a fuel by substituting at least part of a conventional silicon-containing additive using a Fischer-Tropsch derived fuel.

Example 4
Fischer-Tropsch derived gas oil F1 was blended with petroleum derived diesel base fuel F2 in various proportions and the resulting blends and raw fuels F1, F2 were evaluated for defogging properties.

  The defogging test method used is based on ASTM D1094 (“Water reaction of aviation fuels”), but with specific modifications for use with diesel engine fuel. In a graduated cylinder, 80 ml of a fuel sample was mixed with 20 ml of an aqueous buffer solution, shaken vigorously and then left under controlled conditions. The water then separated at the bottom of the sample, and then the appearance of the diesel fuel, interface and water layer was visually evaluated. The loss capacity from the water layer was also visually evaluated.

  The sample preparation was the same as the ASTM method, but the standing time was extended to 4 hours and the evaluation method was modified to recognize 6 rather than haze 4. Furthermore, the fuel layer and the water layer were evaluated separately rather than together as in the ASTM method.

According to the visual evaluation of this method, the top 50 ml of the fuel layer was aspirated from each sample with a pipette and its residual water content was evaluated using a Karl Fischer meter. This allows further identification of multiple samples having the same visual scores.
The results are shown in Table 3.

  The visual grades shown in columns 4-6 and the water loss value in column 7 were measured after 4 hours of standing time. For visual grade, the lower the score, the better the performance.

  From the data in Table 3, it can be seen that Fischer-Tropsch derived fuel F1 has better defogging performance than petroleum derived fuel F2, and can blend with F2 to improve F2 defogging performance. The water content after standing for 24 hours is the most sensitive measure of defogging performance, and F1 clearly shows an advantage over F2 in this experiment.

Example 5
Example 4 was repeated except that F1 was compared to the petroleum derived fuel F4 described in connection with Example 2. The defogging results are shown in Table 4 using the same format as the data in Table 3.

  As before, the defogging performance of F1 was much better than F4, and the blend of F1 and F4 improved the defogging performance of this base fuel.

Example 6
The defogging performance of F1 was compared to the diesel base fuels F3-F7 tested in Example 2 using the methods of Examples 4 and 5. The results are shown in Table 5.

  As before, the Fischer-Tropsch derived fuel F1 is particularly superior to other diesel fuels in the 24-hour residual water content. Fischer-Tropsch fuel F1 alone has excellent defogging (water removal) properties even in the absence of defogging agents, and therefore as an additive-free fuel or at least as a defogging agent-free fuel, Alternatively, it can potentially be used as a fuel with few additives. When blended with other fuels with poor defogging properties, Fischer-Tropsch fuel alone may be used as a defogging agent. Such blends, as mentioned above, may contain low levels of additives, especially defogging agents, or may not contain any at all, and in fact provide acceptable defogging performance for the base fuel. Some or all of the conventional defogging agents that may need to be replaced can be substituted.

  Examples 1, 2, and 4-6 all show the defoaming characteristics and defogging characteristics of Fischer-Tropsch derived fuel. This dual effect makes this type of fuel suitable for replacing both types of additives, thus having a low total additive level, perhaps no additives at least, or at least antifoam and defogging. It is possible to obtain a fuel composition that contains or preferably does not contain the agent at a low level.

  Fischer-Tropsch derived fuels, particularly gas oils, have cleaning properties and reduce fuel-related deposits in the engine where the fuel composition is introduced and / or remove previously generated engine deposits It has been found useful in the composition. In other words, Fischer-Tropsch derived fuel has been found useful to keep the engine clean and even improve by contributing to reducing and / or eliminating fuel injector contamination. For these reasons, a Fischer-Tropsch derived fuel or a fuel composition containing the derived fuel can reduce any level of cleaning agent and, as before, a fuel composition that contains no or substantially no additives according to the present invention. The possibility of things can be increased.

In addition, the composition containing the Fischer-Tropsch fuel component also creates the opportunity to use a defoamer that does not contain silicon due to the need for a lower detergent level, further reducing the overall silicon level and thus engine contamination. Has the associated advantage of being reduced. As mentioned above, there is a potential for fuel compositions that do not contain any silicon.

Claims (10)

  A method of using a Fischer-Tropsch derived fuel in a composition for the purpose of reducing the amount of additives other than detergents in the fuel composition.   The use according to claim 1, wherein the Fischer-Tropsch derived fuel is used for the purpose of reducing the amount of antifoam and / or defogging agent in the composition.   Use according to claim 1 or 2, wherein the Fischer-Tropsch derived fuel is also used for the purpose of reducing the amount of cleaning agent in the composition.   A method of using a Fischer-Tropsch derived fuel in the composition for the purpose of reducing the amount of silicon in the fuel composition.   A method of using a Fischer-Tropsch derived fuel in a composition for the purpose of improving the defoaming and / or defogging properties of the fuel composition.   The method according to any one of claims 1 to 5, wherein the used Fischer-Tropsch derived fuel does not contain an antifoaming agent.   The use according to any one of claims 1 to 6, wherein the Fischer-Tropsch derived fuel is used in the fuel composition at a concentration of 15% v / v or more.   The use according to any one of claims 1 to 7, wherein the Fischer-Tropsch derived fuel is gas oil.   The use according to any one of claims 1 to 8, wherein the fuel composition is a diesel fuel composition. i) contains a Fischer-Tropsch derived fuel and a defoamer that is free or substantially free of silicon, optionally with one or more other fuel components, preferably free of detergents, or ii A) Defoamer containing a Fischer-Tropsch derived fuel and one or more fuel additives, preferably non-cleaning additives, optionally together with one or more other fuel components And / or no silicon-containing antifoam and / or no defogging agent, preferably no detergent, or iii) Fischer-Tropsch derived fuel and one or more fuel additions A non-detergent additive, optionally with one or more other fuel components, and no defogging agent, or iv) Fischer-Tropsch derived fuel And one or more non-detersive fuel additives, together with one or more other fuel components, optionally containing substantially free or free silicon,
Fuel composition.